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Pfizer announced on Saturday its tweaked COVID-19 shots to target the Omicron variant have demonstrated substantially higher protection against the coronavirus.
As the Omicron variant continues to spread across the country, Pfizer and its partner BioNTech have studied the impact of their updated boosters on the immune system to fight the contagious mutant.
One test involved a booster targeting Omicron specifically, and the other targeted both Omicron and the original virus. More than 1,200 middle-aged and older adults who volunteered to be involved in the study experienced massive increases in neutralizing antibody levels a month after administration, depending on the dose, the companies said.
Candidates who were given Pfizer's omicron-only booster elicited 13.5 to 19.6 times higher Omicron-fighting antibodies. Meanwhile, candidates with the bivalent vaccine exhibited a 9.1 to 10.9 increase. All volunteers appeared to be well-tolerated to the tests in the study.
The results from the studies also suggest the vaccines are adequate for the Omicron BA.4 and BA.5, which are rapidly circulating in the United States, according to the companies' statement.
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"As we've said since the early days of the pandemic, we will follow the science and adapt our own approaches as needed to help address COVID-19 as the virus evolves," Albert Bourla, Chairman and Chief Executive Officer, Pfizer said in a statement. "Based on these data, we believe we have two very strong Omicron-adapted candidates that elicit a substantially higher immune response against Omicron than we've seen to date."
The announcement of the Omicron-adapted vaccine shots comes as the federal authorities are deciding whether to use a tweaked version for a vaccination campaign this fall. The companies will present their latest accumulated data on Tuesday at the meeting between the US Food and Drug Administration's Vaccines and Related Biological Products Advisory Committee.
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Earlier this month, Moderna also released preliminary data stating its new "bivalent" booster shot caused an eightfold increase in neutralizing antibody levels while still being effective against other variants of concern.
"We're pretty confident this vaccine is going to provide a benefit even against the family of omicron subvariants," Moderna President Stephen Hoge told reporters, per The Washington Post.